How farmers can prepare for El Niño

Backgrounder

If you farm in a region that is affected by El Niño, you are probably preparing for uncertain weather conditions.  You may be expecting very wet weather or very dry weather.  Perhaps you are already feeling the effects of heavy rains or drought.  What steps can you take to make sure that you still have food to harvest at the end of the growing season?  That’s what I’m going to talk about today -ways you can reduce the risk of severe crop damage.

I’m going to talk about several ways to save soil and water.  By protecting soil and water you protect crops.  This is important to remember.  If you get heavy rains you must do the best you can to make sure that water does not flow quickly away.  Fast‑flowing water will take your soil with it.  If you are expecting very dry weather you should try to catch and hold as much water as possible on your land.

Here are a few of the things you can do to save soil and water.

Number one.  Keep the soil covered.  When soil is covered it is less likely to be washed away or blown away.  Soil that is covered will absorb more water.  You can keep soil covered with a cover crop.  Cover crops are plants that farmers grow especially to cover and protect the soil. Some cover crops are grown at the same time as the main food crop, while others are grown between seasons when nothing else is growing.  People often use leguminous crops for this purpose because legumes also add nitrogen to the soil.  Some examples of leguminous cover crops are velvet bean (Mucuna pruriens), sunnhemp (Crotalaria spp.), and lablab bean (Dolichos lablab).

Mulch is another good way to keep your soil covered.  A mulch is a layer of organic materials – usually plants that is spread on the surface of the soil.  People commonly use weeds, and grasses, and leftover crop leaves and stems.

Number two.  As well as growing or spreading something on top of the soil, you should also keep lots of organic matter in the soil.  Composted manure is a good source of organic matter. So are leftover crop stems and leaves that you plough into the soil after harvest.  In dry weather organic matter helps soil to hold water.  In wet, rainy weather, organic matter in the soil soaks up water.  This prevents a heavy flow of water from washing the soil away.

Number three. Learn special methods you can use to save soil and water as you cultivate.  For example, if you farm on a hillside, plough along contour lines.  Contour lines are imaginary lines that run across the slope at the same height, but do not run uphill or downhill.  On flat land you can use cross‑ridging.  Make little barriers, called cross-ridges, which cross the furrows at regular intervals.  This creates small basins all over the field.  The basins hold water after a rainfall.  You can also plant windbreaks and grass hedges to keep soil in place.  Vetiver grass (Vetiver zizanioides) is one plant that is widely used in hedges to prevent soil erosion.
These are just a few examples of soil conservation techniques.  There are many more.

And here’s the fourth thing to consider.  Remember that trees can help you to protect soil, water, and crops. Trees affect the way water moves into and through the soil.  As tree roots grow they make channels for water to move through.  Tree branches and leaves stop raindrops from hitting the ground very fast.  So there is more time for the soil to absorb the rain water.  Because less water will wash away, you lose less soil.  Trees provide shade too.  More shade means that less water evaporates from the soil.  This is particularly important in hot, dry areas.

In places where there are not many trees, there are often water shortages.  Rainwater will not stay in the soil, especially in hot areas.  It will evaporate quickly into the air or it will move along the soil surface carrying away the topsoil.  The soil will become poor and infertile.  Planting trees will help you reduce these problems.

One more thing.  Another way to keep crop losses as low as possible is to plant many different types of crops and crop varieties.This is called diversification.  This way if you have bad weather you may experience damage to one or two crops.  But if you have many different types and varieties planted, you will still have other crops that survive and yield well.

If you have already suffered losses this season these suggestions might not be helpful right now.  But if you start using these methods now you will be rewarded in the future.  Over the years you will see an improvement in your soil.  You will have better yields and healthier crops. The next time bad weather hits you might not suffer as much.  And your children and grandchildren will certainly benefit from your good management of these precious resources – soil and water.